A 0.2-mW 2-mb/s digital transceiver based on wideband signaling for human body communications

Abstract

This paper presents a low-power wideband signaling (WBS) digital transceiver for data transmission through a human body for body area network applications. The low-power and highspeed human body communication (HBC) utilizes a digital transceiver chip based on WBS and adopts a direct-coupled interface (DCI) which uses an electrode of 50-Omega impedance. The channel investigation with the DCI identifies an optimum channel bandwidth of 10 kHz to 100 MHz. The WBS digital transceiver exploits a direct digital transmitter and an all-digital clock and data recovery (CDR) circuit. To further reduce power consumption, the proposed CDR circuit incorporates a low-voltage digitally-controlled oscillator and a quadratic sampling technique. The WBS digital transceiver chip with a 0.25-mu m standard CMOS technology has 2-Mb/s data rate at a bit error rate of 1.1 X 10(-7), dissipating only 0.2 mW from a 1-V supply generated by a 1.5-V battery.